Chapter 38: Angiosperm reproduction and biotechnology Flashcards
asexual reproduction
produces offspring from a single parent without the fusion of egg and sperm
clone
genetically identical offspring
fragmentation
severed parent plant leads to two individuals
adventitious shoots
form of asexual reproduction (aspen)
apomixis
seeds produced by mitosis without fertilization
advantages of asexual reproduction
doesn’t require another individual, no frail seedling, pass on exact genetic info
disadvantages of asexual reproduction
pass on exact genetic info
selfing
sexual reproduction within a single plant; self-fertilization. Same disadvantages as asexual
dioecious
plants are one sex or the other
totipotent
meristematic cells that are able to divide and differentiate to form a new plant
callus
clump of totipotent cells
grafting
physically combining two plants
stock
plant that provides root
scion
plant grafted onto the scion
flowers
reproductive shoots of the angiosperm sporophyte
receptacle
where flowers attach to stem
sepals
outermost ring, usually green; sterile
petals
attract pollinators; sterile
stamens
male flower parts (microsporophyll); fertile
carpels
female flower parts (megasporophyll); fertile
anthers
part of stamen (on filaments) that contains microsporangia (pollen sacs) that produce pollen
stigma
sticky part of carpel that captures pollen
style
connects stigma to ovary
pistil
carpel or group of fused carpels
complete flower
all 4 floral organs
incomplete flower
<4 floral organs
pollination
transfer of pollen from anthers to stigma; wind, water, animals
pollination syndrome
characters developed by plants related to pollinators
coevolution
joint evolution of two or more interacting species in response to selection imposed by each other; plants and pollinators
pollen grain
(n) microspore divided into generative cell, tube cell, and spore wall
microspore
(n) make pollen, derived from microsporocytes
microsporocyte
(2n) each make 4 microspore
microsporangia
pollen sacs; 4 per anther
ovary
ovules with megasporangium
megaspore
(n) of the 4 megaspores made by the megasporocyte, 1 survives; nucleus divides 3x creating 8 nuclei
megasporocyte
(2n) makes 4 megapores
8 nuclei of megaspore
3: micropyle- egg + 2 synergids
3: antipodal cells- other end of the ovule from micropyle
2: polar nuclei (without membrane)
double fertilization
pollen grain contacts stigma, tube cell forms a pollen tubes that grows down the style. generative cell divides into two sperm: 1 fertilizes the egg (zygote 2n), 1 fertilizes the polar nuclei (endosperm 3n)
benefit of double fertilization to parent
doesn’t have to waste nutrients on unfertilized eggs
benefit of double fertilization to seed
provides endosperm of nutrients
embryonic development
occurs in the seed; zygote becomes embryo, asymmetrical division of basal cell and terminal cell: larger basal cell becomes suspensor and smaller terminal cell becomes proembryo, cotyledons develop
hypotcotyl
eudicot cotyledon; lower part connects to radicle (embryonic root)
epicotyl
eudicot cotyledon; upper part, immature roots (embryonic shoot)
scutellum
cotyledon of monocots
coleoptile
sheath surrounding embryonic shoot of monocot
coleorhiza
protects embryonic root of monocots
last stage of seed development
seed ejects most of its water and closes the micropyle, allowing it to remain dormant until ideal conditions
imbibition
uptake of water that begins germination; expansion causes seed coat to rupture
eudicot germination
radical emerges first, followed by the hypocotyl, then epicotyl
monocot germination
coleoptile protects shoot and leads the way up
fruit development
simultaneous with seed; triggered by double fertilization
pericarp
developed ovary wall
simple fruit
single carpel
aggregate frut
multiple carpels of one flower
multiple fruit
multiple flowers
accessory fruit
other flower parts incorporated into fruit
abiotic dispersal
wind and water
biotic dispersal
animals
crossbreeding
favorable traits crossed between wild type and domestic variety
GMO
genetically modified organisms; natural or intentional
CRISPR
technology used to directly transfer genes of plants
biofortification
improve the nutritional quality of plants
biofuel
fuels derived from living biomass